Description

The documentation of log4net points out that the logging of caller location information can be very slow and shouldn't be used unless the performance of the software is not affected. And until the Windows 10 Fall Creators Update this was the case.

But after the Windows update (1709) the performance with caller location information like %C %M %L is about 100 times slower than without. The following results are based on the simple Visual Studio project attached to this issue.